Tintin is handed a file and cuts though two sturdy iron or steel bars in front of the prison window within at most a few hours, to make his escape before sunrise. Cutting even one such bar with a mere file would take at least a day for the filing alone, which he would need to interrupt whenever there was a risk of any guards noticing.
It makes no sense for the professor of archaeology not even to bring a single shovel when he is going on an archaeological dig in the Egyptian desert, nor any other equipment, let alone an appropriately sized expedition.
When Tintin and Snowy are running toward the plane with the rifle man on guard, Tintin employs the ruse to shout "Save me! The dog has rabies!" It makes no sense for the gun man not to shoot Snowy and it makes no sense for Tintin to take the risk of getting Snowy shot.